Electric switch



Patented Nov. 22, 1921.

P. F. woLLENwEBER.

ELECTRIC SWITCH.

APPLICATION FILED APR25| 1918.

UNITED STATES PATENT' OFFICE.

PAUL F. WOLLENWEBEB, OF TOLEDO, OHIO, ASSIGNOB TO EILEGTB'IGA AUTO-LITE COR- -POBATION', OF TOLEDO, OHIO, A ACORPORATION' OF DELAWARE.

ELECTRIC SWITCH.

Specicaton of Letters Patent.

Application led April 25, 1918. Serial No. 230,712.

To all 'whom it may concern.:

Be it known that I, PAUL F. WOLLEN- WEBER, a citizen of the United States, residing at Toledo, in the county of Lucas and State of Ohio, have invented certain new and useful Improvements in Electric Switches, of which I declare the following to be a full, clear, and exact description.

This invention relates to electric switches of the longitudinally reciprocating type, and is particularly applicable for use in connection with a heavy current circuitsuch as is employed in starting internal combustion engines.

The principal object of the invention is to provide a switch of the above named type possessing novel means of effecting the back kick or release.

Another object is to vproduce a switch in which full pressure Contact is automatically maintained at the electrical terminals until the exact moment of release.

Further objects of this invention relate to economies of manufacture and details of construction as will hereinafter appear from .the detailed descriptionto follow. I accomplish the objects of my invention in one instance by the devices and means described' in the following specification, but it is evident that the same may be varied widely without departing from the scope of the invention, as pointed out in the appended claims. A structure constituting one etnbodiment of my invention, which may be the preferred, is illustrated in the accompanying drawings forming a part thereof, in which: Y

Figure I is a top view of'the assembled switch.

Fig.`II is a plan view ofthe switch with the top of the casing removed and parts in section.- Y

Tig. III is a sectional elevation of the switch taken' on the line III-III of Figs. I, II and IV.

F ig. IV is a sectional elevation on the line IV-IV of Figs. I, II and III.

Fig. V is a view, similar to F ig. IV, showing the parts in operative relationwhen the plunger is depressed.

Fig. VI is a detail view in side elevation of one member of the locking device, and

Fig. VII is a detail, perspective view of the other member of the locking device.

serted through the plunger.

In the drawings, similar reference numerals refer to similar parts throughout the several views, and the sectional views are taken looking in the direction of the small arrows at the ends of the section lines.

As illustrated, I provide a plunger rod 1 of appropriate length, to the upper end of which is attached an operating button 2 by a rivet 3. Below the middle of the rod, a notch 4 is made in the rod, the lower edge of which forms a cam surface 5 and the upper edge 6, an abrupt laterally projecting wall. Just above this notch a pin 7 is in- The ends of the pin project beyond the plunger surface for a purpose hereinafter described.

The plunger is adapted to have axial movement in a short cylindrical sleeve 8, shown in detail in Fig. VI. The lower half of the cylinder is squared on three sides, (as best shown in Fig. II) the axial center of the squared portion being offset from the 'cylinder axis to such an extent that the center plane surface 9 is nearest the' cylinder axis and a vertical slot 10 is cut in the said surface.

A groove 11 is made in the upper end of th'J plane surface 9 and the cylinder immediately above the groove is cut to form a slanting plane face 12 (Fig. VI). Another groove or slot 13 is cut axially in the upper cylindrical portion of the sleeve, the plane of the slot lying parallel to the center plane surface 9. When assembled, the plunger has sliding movement in the cylinder, with the ends of the projecting pin lying in the groove 13. When the'pin lies at the base of the groove, the upper wall 6 of the notch in the plunger is parallel with the upper wall of the groove 11, as shown in Fig. V.

The means for holding the switch in contact position comprises a plate .14 with anI elongated aperture 15 in which the squared portion of the sleeve 8 is adapted to slide. Integral with the ends of this plate are outwardly extending projections 16 and 17 which have bearing in the walls of the casing 27. A compressed spring 18 is coiled about the projection 17 of the plate and tends to move the plate against the plane surface 9, so that, when the plate registers with the groove 11, it moves into the groove,

locking the sleeve in place and resting in the cut-out portion 4 of the plunger adja- -cylinder* 22, closed at its lower end, and

y its full force to separate'the'contact surfaces cent the upper wall thereof. `The cut away portion 12 permits easy insertion of the by means of a strip 19 of sheet co per, havv ing a central aperture 2O .(Fig. II through which theplunger 1 projects, and the strip 19 is insulated from the sleeve 8 by means of a strip of insulation fiber 21.

The end of the plunger slides in a hollow having an outwardly extending flange 23 at its upper end. A strip of non-conducting fiber 24 insulates the flange 23 from the contact plate 19.

The end cylinder 22 has vertical movement in the base of the casing 27. Terminal electrodes 25 and 26 are 'attached to the base of the casing 27, which, in the vpresent form ofl my invention, consists in av narrow box of sheet metal to which a -lid or top 28 with a cup stamping 29, integrally forned, is attached. The plunger passes through an aperture formed centrally in the base of the cup '29 and is held in normal position by means of an encirclin spring 30 and by means of the pin 7. Similarly, the end c ylinder 22 is held in elevated normal positlon on the base by means of a coil spring 31, compressed between the flange 23- of the cylinder and the base of casing.

The terminal contacts 25 and 26 take the form of bolts having flattened heads 32 and screw ends 33 with nuts 34 adapted to hold the bolts in'position on the casing, and the connectors 35, in close contact with the bolts.

The bolts are insulated from the casiig byA the means of the insulation lining 36 an insulation washers 37 and 38. A The operation of the switch will now be described. During the initial downward movement of the plunger rod against the com ression spring 30, the pin 7 moves free y in. the slot 13 of the sleeve 8 until itA rests at its bottom. Movement is then -im-L parted to the Contact plate 19, through the sleeve, against resistance of the compression spring 31. At the point of complete contact 'of the plate with terminal bolts 25 and 26,

the sliding bar moves into the groove 11 on the sleeve and seats in the notch 4 in the plunger rod l, and uniform compression is thus maintained at the extreme downward position of the' plunger. When the pressure on the rod head 2 is removed, the rod begins an upward movement through expansion of the spring 3() and, due to the vertical portion of the notch 4 in lthe rod 1, the-locking bar 14, compressed by its spring/ 18, remains seated in the sleeve slot 11, until the lower inclined end of the notch moves the bar out of the groove 11, when the spring 31 exerts and eii'ect a clean, quick break. l

The switch above described is especially advantageous for heavy current duty, where low resistance and non-arcing characteristics are required.

I am aware that the particular embodiment of my invention, herein shown anddescribed, is susceptible of considerable variation without departing from the spirit of my invention, and, therefore, I desire to claim the same broadly, as well as specifically', as indicated by the appended claims. Y p

- .Having thus described my invention, what lI claim as new and desire to secure by Letters Patent, is v 1. In an electric switch, the combination of a casing, having a pair of contacts secured thereto, a rod slidable in said casing, a sleeve loosely mounted onsaid rod, a member carried by said sleeve and adapted in one position to bridge said contacts, a spring tending to hold said member away from said contacts, latching means carried by said casing for holding said sleeve against movement in either direction and means on said rod for. releasing said latching means when the rod is moved to la predetermined position.

2. In 4an electric switch, the combination of a casing having a pair of contacts secured thereto, an o-perating rod slidable in said casing, a sleeve adapted to have limited sliding movement on said rod, a member carried by said sleeve for bridging said contacts when said rod is depressed and a latch for holding said bridging member in contact position, said sleeve and said rod having recesses positioned to be brought into alinement to receive said latch, the recess on said rod having a cam portion to engage and move said latch out of holding position when the rod is moved to release position.

3. In an electric switch, the combination of a casing; a plurality of binding post terminals in said casing and insulated therefrom; a contact bar adapted to bridge said terminals; an actuating plunger movable axially through said casing; resilient means tending to resist motion of said plunger; a pin extending through the plunger; a sleeveV movablefon the plunger, having a slot in which the.l pin is adapted to move; a hollow 115 cylinder slidable through the base ofsaid casing, in which the plunger has slidable movement and resilient means tending to resist movement of said cylinder.

4. In an electric switch` the combination of 120 a casing; av plurality of binding post terminals in said casing and insulated therefrom; a contact bar adapted to bridge said terminals; a plunger rod movable in said casing; resilient means tending to resist 125 movement of the plunger rod; a pin extending through said'plunger rod; a. notchcut in said plunger rod having a lower cam edge; a sleeve slidable on the plunger rod having its upper end slotted to receive the 130 pin and its lower end squared; a transverse groove in the squared portion of the cylinder; a locking bar having a transverse portion adapted to seat in said transverse groove when in locking position; resilient means tending to force said bar into the transverse groove; a hollow cylinder slidable through the base of the casing, forming a support for the contact bar; and resilient means tending to force the cylinder into the casing. 5. In. an electric switch, the combinatio of a stationary Contact, a movable contact, a sleeve engaging said movable contact and having a groove, a plunger rod projecting through said sleeve, having a notch with a cam surface and adapted to move said sleeve for the purpose of moving said movable contact into engagement with said stationary contact, and a locking device movable into locking engagement with said groove and movable out of said groove by said cam surface' after the plunger rod has been moved relative to said sleeve' to effect a clean, quick break between the contacts.

6. In an electric switch, the combination of stationary contact means, movable contact means, a locking device, actuating means for the movable contact, means comprising a movable member having a groove and a second movable member having a notch with a cam surface, the second member being adapted to move the first member in one direction so that the groove and notch are brought into coperative relation with the locking device at the same time and the second member being adapted to initially move in the reverse direction relative to said first member whereby said cam surface moves the locking device out of said groove.

In testimony whereof, I aix my signature.

PAUL F. WOLLENWEBER. 

